El Cap took about an hour to download and install. Only glitch was CS5 needed a Java update and I needed an update for the Photoshop plugin, Topaz Adjust. Apps were slow to load and open at first but appear to work as normal now. Continuing with fingers crossed.

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This is where I'd normally write an impressive summary of my skills and proficiencies.

OK. So I installed OS X 10.11 El Capitan on my Late 2013 MacBook Pro and have been using it for a couple of days. For me, I have not found any issues.
Since my FileVault was already turned off, it did not get turned back on again. Yeah.
In fact I did not see that Start Using FileVault screen after booting up the upgrade like I did in 10.10.5 Yosemite.

There are many articles online about El Capitan. Sadly they're all sites full of ads, and some have that detestable autoplaying video. Fortunately, Safari 9 has a mute button on any tabs with playing audio or video. Because you can't always tell which tab is playing video, look at the tabs themselves.

The San Francisco font seems a tad more readable to me, but then I'm using a retina iMac.

Split screen might be handy, especially if you don't have a huge monitor and you're used to using Full Screen mode.

Notes may be a big deal, if one gets used to to using it. Note that you must upgrade on your iOS devices after you get El Capitan installed on your Macs. Some people apparently upgraded before installing El Capitan and found that they couldn't read the new Notes on their Mac. It just makes sense to be able to sketch (Who knew all that finger painting practice would turn out to be useful?), embed photos, etc. Third-party apps have had those features, and you could use a sketching application and copy and paste, but having it all together and with auto syncing is nice.

Secure Empty Trash is gone. Well, it hardly ever made sense, except for a few people and one general purpose, but it's meaningless in the world of SSDs and Fusion drives. You can't overwrite a file on an SSD. And overwriting a file with zeros on a hard drive may not be good enough to defeat the FBI or NSA.
But with the change, we get a bonus: Delete Immediately. You can get it in a contextual menu if you're looking at the Trash Finder window (control click or right click), or from the File menu in the Finder if you hold down Option. From what I've read, the option in the Trash Finder window works for files that won't delete for some reason. (Secure Empty Trash would do that in Yosemite. That's the general purpose I mentioned above.)

The ability to shake the mouse pointer to make it jump out at you is great, but I have to shake it way too much. I'd love a setting for the sensitivity of this great feature. We still have the cursor size setting, so you can set your mouse cursor to be a tad larger than normal.

There are probably many more little refinements I haven't noticed, and El Capitan has lots of changes under the hood, including Security enhancements.

The only downside I've seen is the 6 GB download.

"Design is not just what it looks like and feels like. Design is how it works."
Steve Jobs

Finally decided to bite the bullet and install El Capitan. It took many hours (!!!) to download on my 55 mb/s internet connection which surprised me because it's usually a pretty quick line. All seems well and have not encountered any bad things so far. As a relief that others might also find interesting... I note that iPhoto works properly as it did under Yosemite. Those struggling with Photos I would still counsel to find a way to continue using iPhoto.